Don't fatal error during initialization for missing service providers

Sometime during the split, code was added to fixup driver paths,
which imports service providers even for plugins which are not
in use. That, combined with neutron including default service
providers for VPN and LOADBALANCER, resulted in a really messy
mess in terms of removing VPN from the main neutron test suites.

This change stops the imports, so that if one of the services is
missing, neutron server can still start. It likely breaks the driver
path fixup, which can be fixed outside of this gate blockage.

Closes-Bug: #1483266
Change-Id: I23f9007357d8cbbae599997c244561a4e2f32ce1

diff --git a/neutron/services/provider_configuration.py b/neutron/services/provider_configuration.py
index cc406e74193ae2668f8725ce9134078fa120f4a4..938644f8c47d556653f155c800a19355eb6907f4 100644 (file)
--- a/neutron/services/provider_configuration.py
+++ b/neutron/services/provider_configuration.py
@@ -51,6 +51,8 @@ def get_provider_driver_class(driver, namespace=SERVICE_PROVIDERS):
     try:
         driver_manager = stevedore.driver.DriverManager(
             namespace, driver).driver
+    except ImportError:
+        return driver
     except RuntimeError:
         return driver
     new_driver = "%s.%s" % (driver_manager.__module__,